Autoradiography of the uptake and localization of calcium 45 by urodele embryos during the process of neurulation. Scanning electron microscopy of the migration of the neural folds of urodele embryos whose neural plates have been surgically removed. An examination of the biochemical moities of the surface of the chordamesoderm important in the migration of these neural folds. Scanning electron microscopy of the outgrowth of aggregates of pigmented retinal epithelium on 4 cellular substrata, correlating this morphology with the biochemical observations currently being made.